This invention relates to a two-stage type enclosed switchboard, and more particularly to the arrangement of instruments on the switchboard surface and the division and structure of the doors.
In recent years the apparatus that is accommodated in enclosed switchboards or metal-enclosed switchgear has been made progressively smaller, as have enclosed switchboards and two-stage or two-tier integrated enclosed switchboards accommodating two circuit breakers one above the other. It is no exaggeration to say that most of the enclosed switchboards that are now being made are of this kind. On the other hand, in two-stage integrated enclosed switchboards the door has usually been divided into two parts, one above the other, and the instruments for the protection and inspection of the respective apparatus have now been mounted on the door surfaces. But in this case, the space for mounting the instruments has been reduced to half of what it was and therefore the arrangement of the meters and relays, operating switches, lamps, testing terminals and the like has become a problem. As regards the operating switches, for example, if these are mounted on the top door they are too high and therefore cannot be reached by hand and this causes trouble, whereas if they are mounted on the lower door they are too low and as a result it is not easy to operate them. This does not apply only to the operating switches; the same can be said of the meters, lamps, testing terminals and the like. On the top door these instruments must be mounted at the bottom, and on the bottom door these instruments must be mounted at the top. Accordingly, even if the top and bottom circuits are exactly the same, the apertures in the doors and the mounting and arrangement of the instruments are different and this is, therefore, inconvenient from the point of view of standardization.